Optimum tool planning using the X-factor theory

Recently there has been a strong story emphasis in the semiconductor industry on "time to market" and "low cost" which require short cycle time and high utilization of a minimum number of tools, respectively. There is a trade-off between cycle time and utilization. By defining utilization of tools and implementing to X-factor theory, authors developed a useful method of tool planning that meets the requirements of short product cycle time and highest output by reducing the risk of processes or tools causing bottlenecks which are applicable to all semiconductor factories.